This invention relates to a surgical microscope which enables the position of a medical instrument used under the surgical microscope to be sensed reliably.
In microsurgery where a fine operation is performed under a surgical microscope, before an operation, an operation plan has been made in recent years on the basis of tomographic images. In addition, surgical instruments have been undergoing improvement with an eye to making effective use of the tomographic information even during the operation to assure a safe operation.
In the field of brain surgery in particular, the observation position under a surgical microscope has been sensed on the basis of tomographic images before an operation and the tomographic image information corresponding to the observation position under the microscope has been obtained.
In the prior art, for example, Jpn. Pat. Appln. KOKAI Publication No. 3-205048 has disclosed the technique for sensing the observation position under a surgical microscope. Jpn. Pat. Appln. KOKAI Publication No. 5-305073 has disclosed means for sensing the operating position as well as the surgical microscope. Jpn. Pat. Appln. KOKAI Publication No. 6-175033 has disclosed position determining means for determining the position within or near the observation visual field. In addition, Jpn. Pat. Appln. KOKAI Publication No. 4-231034 has disclosed the technique for sensing and controlling the position of a surgical instrument by means of a robot manipulator.
A system for integrating the observed site into the tomographic image before the operation has been disclosed as means for sensing the positions of an endoscope, a treating instrument, and a surgical microscope.
In Jpn. Pat. Appln. KOKAI Publication No. 3-205048 and Jpn. Pat. Appln. KOKAI Publication No. 4-231034, to sense a position three-dimensionally by means of the body tube supporting arm of a surgical microscope, a second support arm for supporting the treating instrument or endoscope and sensing the position three-dimensionally or an optical position sensing device had to be installed additionally in an operating room, even when the position of the treating instrument or endoscope was sensed under the microscope. Consequently, the second support arm or position sensing device occupied the operating room additionally.
In Jpn. Pat. Appln. KOKAI Publication No. 5-305073, when the position of the endoscope or treating instrument was sensed together with the microscope, the operating site was complicated, because the microscope tube, operator, other treating instruments, and medical instruments were arranged there. Moreover, the treating instrument or endoscope used under the microscope was often unable to sense the position because the medical instruments positioned near the microscope, the hands and arms of the operator, and the operating site intervened between the signal member and the digitizer.
When the digitizer was installed in an operating room to sense the position of the treating instrument, it was necessary to leave a specific space between indexes marked on the treating instrument. If such a space could not be left, it would be impossible to sense the position because the digitizer picked up the indexes repeatedly. An attempt to overcome the drawback causes the problem of enlarging the indexes marked on the treating instrument.
In Jpn. Pat. Appln. KOKAI Publication No. 6-175033, the body tube is moved according to the indication of the observed site, but the site is not correlated to the tomographic image before the operation. Therefore, it is impossible to correlate the tomographic image with the three-dimensional position in the observation visual field of the microscope. Moreover, it is impossible for the treating instrument connected to the manipulator to control the manipulator and give treatments.